Intra- and Inter-Rater Reliability of Strength Measurements Using a Pull Hand-Held Dynamometer Fixed to the Examiner’s Body and Comparison with Push Dynamometry

Abstract

Hand held dynamometers (HHDs) are the most used method to measure strength in clinical sitting. There are two methods to realize the assessment: pull and push. The purpose of the present study was to evaluate the intra- and inter-rater reliability of a new measurement modality for pull HHD and to compare the inter-rater reliability and agreement of the measurements. Forty healthy subjects were evaluated by two assessors with different body composition and manual strength. Fifteen isometric tests were performed in two sessions with a one-week interval between them. Reliability was examined using the intra-class correlation (ICC) and the standard error of measurement (SEM). Agreement between raters was examined using paired t-tests. Intra- and inter-rater reliability for the tests performed with the pull HHD showed excellent values, with ICCs ranging from 0.991 to 0.998. For tests with values higher than 200 N, push HHD showed greater differences between raters than pull HHD. Pull HHD attached to the examiner’s body is a method with excellent reliability to measure isometric strength and showed better agreement between examiners, especially for those tests that showed high levels of strength. Pull HHD is a new alternative to perform isometric tests with less rater dependence.

Psychometric properties of a standardized protocol of muscle strength assessment by hand-held dynamometry in healthy adults: A reliability study

“…However, considering the missing data (no 95% CI provided) and the use of a different protocol in Kilmer's study, comparisons with our results are not possible (36). As for the reliability of the hip internal rotators, a few studies have been conducted with variable results (23,26,37). Unlike our results, Gonzalez-Rosalen et al (23) showed excellent inter-rater reliability.…”

“…As for the reliability of the hip internal rotators, a few studies have been conducted with variable results (23,26,37). Unlike our results, Gonzalez-Rosalen et al (23) showed excellent inter-rater reliability. In contrast, Thorborg et al (37) revealed similar results to ours, with fair to excellent inter-rater reliability and no agreement between testers.…”

“…According to the literature, a SEM of less than 10% is clinically acceptable. (38) Although Gonzalez-Rosalen et al (23) reported good SEM values for 15 muscle groups, their use of Newtons rather than Newton-meters prevents comparisons with other studies, including ours. Also, these SEM values do not consider the error associated with measuring the lever arm, which is key to the biomechanics of strength assessment.…”

“…QMT has good to excellent psychometric properties for different muscle groups evaluated in various populations (9,(14)(15)(16). Indeed, MIMS values obtained with HHD show good concurrent validity with isokinetic dynamometry (9,17,18) and good to excellent reliability for most muscle groups (14,(19)(20)(21)(22)(23)(24). To be con dent that muscle strength changes are true changes rather than the result of measurement error, clinicians should ensure that the measurement error of the chosen outcome measure is small (25).…”

Interrater and Intrarater Reliability of the EasyForce Dynamometer for Assessment of Maximal Shoulder, Knee and Hip Strength

“…EasyForce is purported to allow practitioners to measure muscle force objectively, and thus reducing the need for subjective measures and providing valuable data to aid in the design of treatment plans. Moreover, Easyforce is a dynamometer specifically designed for belt-stabilized HHD, which is of great importance, having in mind that stabilizing dynamometers with belts has shown better reliability and validity [ 34 , 35 ]. However, the vast majority of literature on HHD has focused on devices that are not integrated within the belt.…”